Fastening device for wooden items



y 1966 5' 1.. MAYO ETAL 3,253,759

FASTENING DEVICE FOR WOODEN ITEMS Filed Oct. 16, 1964 2 Sheets-Sheet l I NVENTORS @[0065 1. MA V0 d/MM/E W635 Jaw/0v BY z A TTOQ/VEL May 31, 1966 6.1.. MAYO ETAL 3, 53

FASTENING DEVICE FOR WOODEN ITEMS Filed Oct. 16, 1964 2 Sheets-Sheet 2 0 0 &

INVENTORS 000000 A. MAYO.

- ATTOQA/EK United States Patent O 3,253,759 FASTENING DEVICE FOR WOODEN ITEMS George L. Mayo and Jimmie Webb Jordan, Fort Worth, Tex., assignors to Clary Corporation, San Gabriel, Calif., a corporation of California Filed Oct. 16, 1964, Ser. No. 404,275

8 Claims. (Cl. 227-100) This invention relates to fastener driving devices for fastening wood or the like items together on a mass production basis.

In nailing or stapling wood items, such as door jamb parts, door parts, articles of furniture, etc., which are to be finished, the nails or staples are preferably driven below the surface of the wood and the resulting holes are filled with putty or similar filler paste prior to painting or otherwise finishing so as to hide the fasteners from view.

Generally, in manufacturing wood items on a mass pro-.

duction basis, a fastener gun or stapler is used to drive the nails or staples into the Wood -as the items are fed past a fastening station by suitable conveyor means, and in order to force the fastener below the surface of the wood, the driving element of the gun must also penetrate the wood a certain distance.

Heretofore, it was generally necessary to stop the wood items at the fastening station to allow the fastener drivingelement of the gun to penetrate into the wood and thereafter withdraw before the item could be advanced; otherwise, the driving element would tear or gouge the wood as the latter moved past the driving element during withdr-awal of the latter.

However, the starting and stopping of the conveyor means requires additional control equipment to stop the conveyor means during the time that the gun is fired and the fastener driving element is withdrawn. In cases where a number of guns are used, all such guns must be timed to fire when the conveyor means is stopped. Also, and of majorimportance is the fact that arresting of the conveyor means slows down the overall speed of operation of the mechanism.

Attempts have been made heretofore to overcome this difficulty by moving the fastener gun along with the wood while the fastener is being driven into the wood and during withdrawal of the driving element. Thereafter, the gun is returned to its starting position. Although such means is generally satisfactory, it requires additional and complicated mechanism. Also, such means normally prevents close spacing of'the fasteners since the wood items travel a considerable distance before the fastener gun is returned to its initial position.

It therefore becomes a principal object of the present invention to obviate the above noted difficulties and to enable operation of a fastener gun or the like during continuous movement of work pieces relative thereto.

Another object is to increase the speed of fastening wood or the like items together in cases where the fastener is driven below the surface of the wood.

The manner in which the above and other objects of the invention are accomplished will be readily understood on reference to the following specification when read in conjunction with the accompanying drawings, wherein:

FIG. 1 is a side view of a door jamb assemblying machine embodying a preferred form of the present invention.

FIG. 2 is a transverse sectional view of the machine, taken along the line 22 of FIG. 1, showing one of the staplers and its mount.

FIG. 3 is a plan view taken along the line 33 of FIG. 2.

FIG. 4 is a sectional view through the air control valve for the staplers.

3,253,759 Patented May 31, 1966 FIG. is a sectional view similar to FIG. 2 but with parts broken away, showing the stapler in the act of forcing a staple into the door jamb parts.

The invention is disclosed as embodied in a machine for automatically stapling the parts of a wooden door jamb at spaced points along its length. However, the invention is not limited to such application and may be used to fasten a wide variety of items. 1

In accordancee with general practice, a conventional wooden door jamb comprises an elongate jamb part 11, the side trim parts ,12 and 13, and a door stop part 14. Such parts are generally nailed or stapled at spaced points throughout their length.

As shown particularly in FIGS. 1 and 2, the various parts of a door jamb are placed in a guide chute formed of two channel members and 16 held in parallel spaced relation by a tubular member 17. The chute is supported from the floor by legs 18 and 20 which also carry bearing brackets for shafts 21 and 22, on which are mounted chain sprockets 23 and 24, respectively. The latter support the opposite ends of an endless chain 25, the upper strand of which is guided over the member 17 and intermediate the channel members 15 and 16. Cleats 26 and 27 are attached tolinks of the chain for engaging and driving the jamb components along the chute and past a fastening station generally indicated at 28.

The chain is driven by a motor 30 which is entrained with the sprocket shaft 22 by a speed reducing unit 31 and a chain and sprocket arrangement 32.

Two staplers generally indicated at 33 and 34 are located at the fastening station in alignment with eachother and on opposite sides of the jamb parts to staple the trim parts 12 and 13 to the jamb part 11. A third stapler, not shown, may also be located at the fastener station to staple the stop part 14 to the jamb part.

Such staplers and their mounting means are identical and therefore only one will be described in detail. Referring particularly to FIGS. 2 and 3, the stapler 33 is suitably supported on a horizontal plate 35 which is pivotally supported on a stationary stud 36 extending upwardly from a base plate 37 which is secured to the guide chute.

The stapler is actuated by air under pressure and comprises a cylinder 38 in which is slideably mounted a piston 40 carrying an elongate staple driving blade 41. The latter is guided for endwise movement in a bearing carried by a nose piece 42 on the stapler. A light compression spring 43 surrounds the blade 41 to normally hold the piston and blade in their rearmost illustrated positions shown in- FIG, 2 wherein the forward tip of the blade is located directly behind the lowermost staple 44 of a stack of staples which are slideably mounted in a magazine 45 forming part of the stapler.

Other forms of staples could obviously be employed.

It will be noted that the pivot stud 36 is located on the upstream side of the stapler, relative to the movement of the wooden jamb parts, and the plate 35 is yieldably held in a position directly adjacent the nearest trim part, i.e. 12, by a tension spring 46 in which position the plate limits against a post 47 extending upwardly from the base plate 37. The spring 46 is secured directly to the plate 35 at one end and to an adjustable lug 48 at its opposite end. Such lug is secured to the base plate 37 by clamp screws 50 which extend through elongated slots 51 in the base plate to permit adjustment of spring 46.

The cylinder 38 is connected by-a flexible tube 65 (see also FIG. 4) to the central chamber 51 of a three-way valve generally indicated at 52. A poppet member 53 is slideably mounted in the valve casing and is normally held in its righthand illustrated position by compression spring 54 to locate a roller 55 thereon in the path of a lobe 56 formed on a cam 57 attached to the sprocket shaft 22. In such position of the poppet, a valve element 58 thereon engages a cooperating valve seat on the valve casing to seal off air under pressure from a suitable source of air supply connected to a lefthand chamber 60 of the valve'casing through a tube 61. Also, in such position of the'popp'et a second valve element 62 thereon is held in spaced relation with a cooperating valve seat to permit escape of air from the cylinder 38 through tube 65, chamber 51 and to the atmosphere through a short exhaust tube 63.

During advancement of the jamb parts along the guide chute and past the fastening station 28, and as the cam 57 completeseach revolution, the lobe 56 momentarily moves the poppet53 to the left, permitting a burst of air to be applied through the valve to the piston. Accordingly, the blade-41 engages the lowermost staple 44 and drives it into the adjacent trim part 12 and the jamb part 11, as shown in FIG. 5.

The cylinder 38 is provided with a suitable annular stop shoulder 64 which arrests the piston when the blade 41 has entered a predetermined distance into the trim part 12 so as to drive the staple below the surface of the trim part 12. The resulting hole left in the trim part 12 after the blade 41 is withdrawn is subsequently filled with putty or paste.

It will be noted that the mass of the piston 40 and blade 41 is considerably less than the mass of theremainder of the staplerand its mount. Therefore, since air is admitted to the cylinder in a short burst, the reaction will be such that the piston will be driven forwardly to force the stapleinto the wood. Thereafter, the reaction developed against the increasing resistance met by the staple in entering the wood will cause the stapler to swing about the axis of the stud 36 and in doing so, the shoulder 64 will cause the piston to withdraw the blade 41 from below the surface of the trim part 12. During outward swinging of the stapler, the spring 43 returns the blade within the cylinder so that the spring 46 may again return the stapler to its normal position adjacent the trim part with- .out engagement of theiblade 41 with the latter.

The above noted advancement of each staple into the jamb .parts and consequent retraction of the blade 41 will occur very rapidly so that even though the jamb parts are continuously moved along the guide sheets during the stapling operation, very little, if any, lateral gouging of the wood by the blade 41 will occur. Further, since the pivot stud 36 is located upstream from the fastening station, the blade 41 will tend to move somewhat in the direction of movement of the jamb parts during withdrawal of the blade. w

By appropriate adjustment of the tension of spring 46, the action of the stapler may be adjusted to compensate for wood of different hardness characteristics, etc.

- Although the invention has been described in detail and certain specific terms and languages have been used, it is to be understood that the present disclosure is illustrative rather than restrictive and that changes and modifications may be made without departing from the spirit or scope of the invention as set forth inthe claims appended hereto.

Having thus described the invention, what is desired to be secured by United States Letters Patent is:

1. In a fastening machine forfastening a pair of work 'piecestogether, means for moving said work pieces continuously past a fastening station, a fastener applying device at said station, said device comprising a driving element for driving a fastener into said work pieces and means on said device for propelling said driving element; means guiding said device toward and away from said work pieces, yieldable means normally maintaining said device adjacent one of said work pieces whereby said driving element is effective to drive said fastener below the surface of said one Work piece, the reaction developed by said propelling means in driving said fastener into said workpieces being effective to move said device away from said work pieces, and means on said device for with drawing said driving element from said one work piece during movement of said device away from said Work piece.

2. The structure according to claim 1 wherein said yieldable means comprises a spring.

3. In a fastening machine for fastening a pair of work pieces together, means for moving said work pieces continuously past a fastening station, a'fastener applying device at said station, said device comprising a driving element for driving a fastener into said work pieces and means on said device for propelling said driving element; means for guiding said device toward and away from said work pieces, a stop elementfor limiting. movement of said device toward said work pieces, spring means for normally holding said device against said stop element, said propelling means being effective to propel said driving element a predetermined distance into one of said work pieces when. said device is held against said stop element, and means on said device for withdrawing said driving element from said one work piece during movement of said device away from said work piece, the reaction developed by said propelling means in driving said fastener into said work pieces being effective to move said device away from said work pieces.

4. The structure according to claim 3 comprising means for adjusting said spring to change the force with which said spring holds said device against said stop element.

5. In a fastening machine-for fastening apair of work pieces together, means for moving said work pieces continuously past a fastening station in a predetermined direction, a fastener applying device at said station, said device comprising a driving element for driving a fastener into said work pieces and means on said device for propelling said driving element; means pivotally supporting said device for movement about an axis extending perpendicular to'the direction of movement of said work pieces and toward and away from said work pieces, said propelling means being effective to'propel said driving element a predetermined distance into one of said work pieces, and means on said device for withdrawing said driving element from said one work piece upon swinging movement of'said device away from said work pieces, the reaction developed by said propelling means in driving said fastener into said work pieces being effective t5 swing said device away from said Work piece.

6. The structure according to "claim 5 wherein said axis 'is located upstream from saidfastening station.

'7. A stapling machine for stapling a pair of work pieces together comprising means for moving said pieces continuously past a stapling station, a stapler'at said station,

said stapler including a driving element for driving a staple into said pieces andv means for propelling said driving element; means for guiding said stapler toward and away from said .work pieces, resilient means normally maintaining said stapler adjacent one of said work pieces whereby said propelling means is effective to propel said driving element a predetermined distance into one of said work pieces, means on said stapler for withdrawing said driving element from said one work piece during movement of said stapler. away from said pieces, saidstapler having a greater mass than said driving element whereby'the reaction developed by said propelling means in driving said staple into said pieces will first cause said driving element to enter said one piece and said stapler will thereafter withdraw said driving element from said one piece upon movement of said stapler away from said workpieces.

8. In a fastening machine for fastening a pair of Work pieces together, means for'moving said work pieces continuously past a fastening station, a fastener applying device at said station, said device comprising a driving element for driving a fastener into said work piece and means on said device for propelling said driving element;

5 6 means for guiding said device toward and away from said ment of said device away from said work piece, and the W0f k P PP elemenf for limifing movement of Sald reaction developed by said propelling means in driving devlce toward Sald Work P SPTmg means for normaL' said fastener into said work pieces being effective to move 1y holding said device against said stop element, said said devicfi away from said work piecw propelling means being effective to propel said driving ele- 5 ment into one of said work pieces when said device is held No references cited against said stop element, and means on said device for limiting movement of said driving element into said work FRANK BAILEY Primary Exam-"eh piece, said limiting means being effective to withdraw said driving element from said work piece upon move- 10 GRANVILLE CUSTER, Examiner- 

1. IN A FASTENING MACHINE FOR FASTENING A PAIR OF WORK PIECES TOGETHER, MEANS FOR MOVING SAID WORK PIECES CONTINUOUSLY PAST A FASTENING STATION, A FASTENER APPLYING DEVICE AT SAID STATION, SAID DEVICE COMPRISING A DRIVING ELEMENT FOR DRIVING A FASTENER INTO SAID WORK PIECES AND MEANS ON SAID DEVICE FOR PROPELLING SAID DRIVING ELEMENT; MEANS GUIDING SAID DEVICE TOWARD AND AWAY FROM SAID WORK PIECES, YIELDABLE MEANS NORMALLY MAINTAINING SAID DEVICE ADJACENT ONE OF SAID WORK PIECES WHEREBY SAID DRIVING ELEMENT IS EFFECTIVE TO DRIVE SAID FASTENER BELOW THE SURFACE OF SAID ONE WORK PIECE, THE REACTION DEVELOPED BY SAID PROPELLING MEANS IN DRIVING SAID FASTENER INTO SAID WORKPIECES BEING EFFECTIVE TO MOVE SAID DEVICE AWAY FROM SAID WORK PIECES, AND MEANS ON SAID DEVICE FOR WITH DRAWING SAID DRIVING ELEMENT FROM SAID ONE WORK PIECE DURING MOVEMENT OF SAID DEVICE AWAY FROM SAID WORK PIECE. 